Paraponera clavata

Paraponera clavata
File:Paraponera clavata.jpg
Conservation status
Least Concern (IUCN 3.1)
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Insecta
Order:	Hymenoptera
Family:	Formicidae
Subfamily:	Paraponerinae
Tribe:	Paraponerini
Genus:	Paraponera
Species:	P. clavata
Binomial name
Paraponera clavata (Fabricius, 1775)
Synonyms
Paraponera aculeata (Olivier, 1792) Paraponera tarsalis (Perty, 1833)

Paraponera clavata is a species of ant, commonly known as the bullet ant, named on account of its powerful and potent sting due to its venom. It inhabits humid lowland rainforests from Nicaragua and the extreme east of Honduras south to Paraguay.

Taxonomy

File:Paraponera dieteri specimen.jpg

Paraponera dieteri (pictured) is the only known species that is closely related to Paraponera clavata

Paraponera clavata was first described by Danish zoologist Johan Christian Fabricius, who named it Formica clavata in his 1775 publication Systema entomologiae, based on a worker he collected. Fabricius incorrectly listed its type locality as India, although these ants are only found in South America. French zoologist Pierre André Latreille would later transfer the species to the genus Ponera in 1804. In 1858, the genus Paraponera was established by British entomologist Frederick Smith, who designated Paraponera clavata as the type species by monotypy (the condition of a taxonomic group having only a single taxon described). In this publication, Smith would synonymise multiple taxons under Paraponera clavata, including Formica armata, Formica spininoda, Ponera tarsalis and Ponera clavata. Later publications would also synonymise more taxons, including Formica aculeata and Formica clavata. Until 1994, Paraponera clavata was the sole member of the genus Paraponera and the subfamily Paraponerinae, but the extinct Paraponera dieteri from the Miocene was described by Cesare Baroni Urbani.

P. clavata is commonly known as the bullet ant, the lesser giant hunting ant and conga ant. A local name is hormiga veinticuatro (the "24 ant" or "24-hour ant"), referring to the full day of pain that follows being stung. The specific epithet clavata means "club-shaped".

Description

Worker ants are 18–30 millimetres (0.7–1.2 in) long and resemble stout, reddish-black, wingless wasps. Paraponera is predatory, and like all primitive poneromorphs, does not display polymorphism in the worker caste; the queen ant is not much larger than the workers.

File:Paraponera clavata MHNT.jpg

Paraponera clavata – museum specimen

File:Paraponera scaled.png

Photograph demonstrating the size of bullet ants, with a 2-cm scale bar

Distribution and habitat

Paraponera is distributed throughout Central America and South America, commonly found in the wet neotropic ecozone. These ants are found in Honduras, Nicaragua and Costa Rica from the north, and in Venezuela, Colombia, Ecuador, Peru and Brazil from the south. Colonies are found in lowland areas, at elevations ranging from sea level to 750 metres (2,460 ft). However, specimens have been collected at elevations of 1,500 metres (4,920 ft) in Parque La Amistad.

Colonies consist of several hundred individuals and are usually situated at the bases of trees. Workers forage arboreally in the area directly above the nest for small arthropods and nectar, often as far as the upper canopy; little foraging occurs on the forest floor. Nectar, carried between the mandibles, is the most common food taken back to the nest by foragers. Two studies in Costa Rica and on Barro Colorado Island (BCI) found about four bullet ant nests per hectare of forest. On BCI, the nests were found under 70 species of trees, six species of shrubs, two species of lianas and one species of palm. Nests were most common beneath the canopies of Faramea occidentalis and Trichilia tuberculata, but these trees are also the most abundant in the forest. Nests were present more frequently than would be expected based on the abundance of the trees under Alseis blackiana, Tabernaemontana arborea, Virola sebifera, Guaria guidonia and Oecocarpus mapoura. The large number of nest plants suggests little active selection of nest sites by bullet ants. Small shrubs, however, are underused, probably because they do not provide access to the forest canopy. The study on BCI concluded trees with buttresses and extrafloral nectaries may be selected for by bullet ants.

Parasites

The small (1.5– to 2.0-mm-long) phorid fly, Apocephalus paraponerae, is a parasite of injured workers of P. clavata, of which the supply is constant because frequent aggressive encounters occur between neighbouring colonies, resulting in maimed workers. They are able to parasitise healthy ants if they are artificially restrained, but this is thought to be rare in practice, as healthy ants are agile and able to repel the flies. Both male and female flies are attracted by the scent of injured ants; the females lay eggs, as well as feed, and the males feed and possibly mate with the females. The flies are attracted to a crushed ant within two to three minutes and 10 or more flies may be attracted to each ant. Each ant can harbour 20 fly larvae. Carl Rettenmeyer observed P. clavata actively trying to attack A. paraponerae when they approached the entrance to their nest.

Relationship with humans

Sting

The pain caused by this insect's sting is purported to be greater than that of any other hymenopteran, and is ranked as the most painful according to the Schmidt sting pain index, given a "4+" rating, above the tarantula hawk wasp and, according to some victims, equal to being shot, hence the name of the insect. It is described as causing "waves of burning, throbbing, all-consuming pain that continues unabated for up to 24 hours". The sting is considered to be an effective defence against predators. Poneratoxin, a paralyzing neurotoxic peptide isolated from the venom, affects voltage-dependent sodium ion channels and blocks the synaptic transmission in the central nervous system. It is being investigated for possible medical applications.

Initiation rites

The Sateré-Mawé people of Brazil use intentional bullet ant stings as part of their initiation rites to become a warrior. The ants are first rendered unconscious by submerging them in a natural sedative, and then hundreds of them are woven into a glove made of leaves (which resembles a large oven mitt), stingers facing inward. When the ants regain consciousness, a boy slips the glove onto his hand. The goal of this initiation rite is to keep the glove on for a full 10 minutes. When finished, the boy's hand and part of his arm are temporarily paralyzed because of the ant venom, and he may shake uncontrollably for days. The only "protection" provided is a coating of charcoal on the hands, supposedly to confuse the ants and inhibit their stinging. To fully complete the initiation, however, the boys must go through the ordeal a total of 20 times over the course of several months or even years.

See also

• Myrmecia, often called bull ants, also renowned for their powerful sting
• List of ant genera (alphabetical)

Further reading

• Lattke, JE (2003) - Subfamilia Ponerinae in Introducción a las Hormigas de la Région Neotropical - Von Humboldt Institute, Bogota, Colombia.

External links

• Brief article about Paraponera clavata
• Short article on the bullet ant and poneratoxin
• Giant tropical bullet ant, Paraponera clavata, natural history and captive management, article with images
• YouTube video of initiation ritual
• Paraponera clavata at AntWeb
• [1] data for specimens collected in Grace a Dios, Honduras, the northernmost extent of its range.